<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <meta http-equiv="X-UA-Compatible" content="ie=edge" />
  <title>Document</title>
  <script src="./lib/vue_2.5.22.js"></script>
  <script src="./lib/vue-router_3.0.2.js"></script>
</head>

<body>
  <div id="app">
    <router-link to="/user">User</router-link>
    <router-link to="/register">Register</router-link>

    <!-- 补充代码3: 路由占位 -->
    ?
  </div>

  <script>
    const User = {
      template: '<h1>User 组件</h1>'
    }

    const Register = {
      template: '<h1>Register 组件</h1>'
    }

      // 补充代码1 创建路由实例对象,并定义路由规则
      const router = ?

      // 创建 vm 实例对象
      const vm = new Vue({
      el: '#app',
      data: {},
        // 补充代码2: 挂载路由实例对象
        ?
      })
  </script>
</body>

</html>